NEW YORK — Taylor Swift has been turning heads with her new, sexy wardrobe, but the 23-year-old says it’s just a reflection of getting older.

Swift has people buzzing about her recent red carpet choices, which have included plunging necklines and shorter skirts. “As far as wardrobe, we have been operating from a different place,” Swift said.

While her choices may be demure compared with the Kim Kardashians of the world, for Swift, a former teen sweetheart, it’s raised eyebrows, and she acknowledges that it’s been a bit of a shock for some people who are accustomed to seeing her wear long dresses. She recalled how her decision to wear shorts at last year’s MTV Video Music Awards caused a stir.

“It was like, ‘Gasp, Taylor wears shorts.’ And I thought it was hilarious,” she said, adding: “I’m not going to be like taking my clothes off or that sort of thing.”

Swift’s new look is a reflection of her overall maturation, with her latest album, Red, selling more than 3 million copies since it was released last fall and producing two smash singles, I Knew You Were Trouble and We Are Never Ever Getting Back Together, which is nominated for record of the year at next month’s Grammy Awards.

“I’m so happy about (my) three nominations — it’s so unreal,” Swift said in a phone interview Monday from Paris.

Swift said she’s especially happy with the success of songs like I Knew You Were Trouble, a dance-infused song that takes her further from her country realm than ever before.

“The fans have been so good to me this year,” she said. “I wanted to make a genre-defying record, I wanted to make an album that was hard to pin down, and hard to box in.”

Swift said fans should expect more surprises during her upcoming tour, which kicks off March 13 in Omaha, Neb. She’s partnering with Diet Coke for the tour, and she’s signed on to be a pitchwoman for the beverage.

While a recent op-ed piece in The New York Times questioned whether pop stars should be endorsing soft drinks with society’s push toward a healthier lifestyle, Swift, who noted she’s become more health-conscious, said the beverage is part of her life.

“I think my lifestyle plays a part into what I choose to endorse,” Swift said. “Diet Coke is something that is a part of my life. … Also a part of my life is exercise.”

Her partnership with the soft drink company includes the use of social media platforms to connect with fans, something that Swift, an avid Tweeter and presence on Instagram, already uses on her own.